The father of shamed tennis star Dan Evans has backed Andy Murray's comments on his son, insisting the British No.3 has let everybody down and deserves a ban.

Evans, who reached the last 16 of the 2017 Australian Open -- a career best in grand slams -- tested positive for cocaine during the Barcelona Open this year, sparking outrage from British tennis, including world No.1 Andy Murray.

The Wimbledon champion slammed Evans for his mistake and Evans' dad, David, concedes Murray is correct.

"I have followed Dan around the world to watch him play," said the 62 year old electrician from Birmingham.